黄土的湿陷性与显微结构特征研究——以咸阳市区为例

对咸阳市区黄土湿陷性与微结构的系统研究,发现咸阳市区黄土的湿陷性与微结构特征随地貌单元有不同的变化.渭河三级阶地黄土地层厚度大,湿陷性较强,黄土微结构以支架大孔半胶结结构为主;二级阶地湿陷性次之,黄土微结构以支架大孔-镶嵌微孔半胶结结构为主;一级阶地湿陷性最弱,黄土微结构较为致密,以镶嵌微孔胶结结构和絮凝胶结结构为主.黄土的湿陷性与微结构特征关系密切,支架大孔半胶结结构的黄土湿陷性较强,镶嵌微孔半胶结结构的黄土湿陷性较弱,镶嵌微孔胶结结构和絮凝胶结结构的黄土不具湿陷性.

Study of Collapsibility and Micro-textures of Loess——Taking the Loess in Xianyang Downtown Area As An Example

Detailed micromorphological analysis indicates that the collapsibility and micro-texture of loess varied with the geomorphic unit in Xianyang downtown area.The collapsibility of thicker loess is intensity with the supporting-macrospore and semi-cementation texture in the third terrace of Weihe river.The collapsibility of loess is sub-intensity with the supporting-macrospore and mosaic-microspore and semi-cementation texture in the second terrace of Weihe river.The collapsibility of loess is the weakest with the compact micro-texture,which mainly is characterized by mosaic-microspore and flocculent cementation texture in the first terrace of Weihe river.Based on above analyzed results,it can conclude that there has a high relationship between the collapsibility and micro-texture of loess in Xianyang Downtown area.Loess with the supporting-macrospore and semi-cementation texture has the intense collapsibility,ones with the supporting-macrospore,mosaic-microspore and semi-cementation texture has the sub-intensity collapsibility,and ones with the mosaic-microspore and flocculent cementation texture has not the collapsibility.